A review on evaluation of technetium-99m labeled radiopharmaceuticals Muhammad Usman Akbar 1,2 • Muhammad Razeen Ahmad 3 • Aqeela Shaheen 4 • Sajid Mushtaq 5 Received: 10 December 2015 Ó Akade ´miai Kiado ´, Budapest, Hungary 2016 Abstract In the past few years, substantial progress has been made in technetium chemistry, including the synthesis of a variety of 99m Tc-radiopharmaceuticals. This synthesis can be made feasible by using suitable reducing agents, highly specific ligands, appropriate buffer, and specific pH etc., which results in high radiochemical purity, minimum labeling time, commercial expediency of 99 Mo/ 99m Tc generator and high biological efficacy. 99m Tc-radiopharmaceuticals have confirmed their worth in every span of life, especially in clinical and medical applications. Now 99m Tc based phar- maceuticals are being used as diagnostic agents for a large number of infections caused by bacteria or any pathogens, tumors, cancers, ulcers etc. In this review, we discuss syn- thesis of a variety of 99m Tc carrying biological molecules (antibiotics/antibodies/peptides/amino acids/macro and micro- organic molecules) along with their applications, to overview key innovations. Keywords 99m Tc Á Labeling Á pH Á Antibiotics Á Antibodies Á Peptides Á Amino acids Introduction In radiopharmaceuticals, the radioactive tracers are the main components to examining the function of body systems. Many radiopharmaceuticals are available for imaging pur- poses, which differ in terms of their physical characteristics, bio-distribution and radiation exposure. Medical images provide very helpful information to medical specialists for taking the important and right decision for diagnosis and therapeutic action. The overwhelming applications of radioisotopes in every span of life like agriculture, industry, chemistry, biology and nuclear medicine have made them critically significant. In some diseases radiopharmaceuticals can identify medical abnormalities at an early stage than other diagnostic tests. Synthesis of new radiolabeled agents (radiopharmaceuticals) is the major field of interest of nuclear medicine. Many radionuclides exist in nature, but naturally occurring isotopes do not have suitable half-life for medical use. Radiopharmaceuticals are being used in med- ical applications for molecular imaging and treatment of various infections, cancer and tumor [1–5]. As far as molecular imaging is concerned, it is a distinct technique capable to visualize, characterize and measure the biological processes at the molecular and cellular level, in humans and other living systems [6–13]. Nonetheless, the major radionuclide used for preparing diagnostic radiopharma- ceuticals today is 99m Tc, owing to its physical and chemical properties [14–16]. Salient features of 99m Tc Depending on clinical requirements, gamma or positron emissions, radiolabeling approaches, kinetics and coordi- nating systems, a variety of radioisotopes have been explored to develop radiopharmaceuticals. Among these, & Muhammad Usman Akbar usmanakbar204@gmail.com 1 Department of Chemistry, Government College University, Faisalabad 38000, Pakistan 2 Department of Applied Chemistry and Biochemistry, Government College University, Faisalabad 38000, Pakistan 3 Department of Bioinformatics and Biotechnology, Government College University, Faisalabad 38000, Pakistan 4 Department of Chemistry, Faculty of Science, The Islamia University of Bahawalpur, Bahawalpur 63100, Pakistan 5 Department of Radiation Biotechnology and Applied Radioisotope Science, Korea University of Science and Technology, Daejeon 305-350, Republic of Korea 123 J Radioanal Nucl Chem DOI 10.1007/s10967-016-5019-7